I am looking forward to seeing the results of this survey.  Since 1996 and the beginning of online banking & brokerage, I have believed they ought not to be separate.   

While bundling stock trading activities with personal finances may be generally viewed as more convenient than using online brokerage services, Javelin Strategy’s comprehensive, ongoing survey regarding online banking and stock trading revealed rather interesting responses to this issue.

Source: Javelin Strategy and Research » Online Trading: Banks or Brokerage?

I see three levels of customer requirement:

1. bill payment, online trading, customer service, basic advice
2. financial planning, and direct link to a planner, investment advisor
3. full service brokerage, private banking

When viewed this way, the need to operate as two separate applications, both of which ignore private banking makes no sense from a customer perspective.